The act of defecating directly into one's vagina. Like a space ship attempting to dock to a space station, "space docking" involves very accurate control and near-perfect alignment of the two orifices.

the once common, now lost art of pooping into a girl's vagina, space docking is enjoying a resurgence of popularity, particularly in the midwestern and northeastern United States (most notably Chicago and New York City) that reminds many art historians/scatologists of the beginning of the renaissance that began in Italy in the 15th Century.

Sally didn't much appreciate Charlie's failure to disclose that he ate three bowls of chili before space docking with her last night.

Two objects namely one uncircumcised penis, and one other penis gently come together into a tip to tip union. once touching, the uncircumcised male then proceeds to encapsulate the other mans shaft creating a perfect vacuum seal.

Me and my jew bro went space docking last night... i was stuck for hours.

2. the act of a person or inserting feces into the vagina of another female person.

3. the act of a person or animal defecating into the ass or vagina of another person or animal, the recipient of which then excretes the feces they just received back into the donor anus, this cycle usually continues until someone is sexually gratified.

Yes in the Aristocrats movie a comedy writer explains that space-docking is where you take a shit in a girl's pussy...however I believe there is a more accurate description...
"Okay, obviously there's a bit of confusion here, after reading the video and comments. "Docking" is when a man rolls his foreskin over another man's penis. Using a frozen shit (usually in a condom) as a dildo is an Alaskan Pipeline. Space-docking is when one person shits in to another person's ass and they pass the shit back and forth between each other, shitting it in to each others' asses. Kind of like Lady and the Tramp, but only with shit instead of spaghetti."
-petrofang
a comment on you tube video - GaBDZEMmJHA